Arkansas coach Bret Bielema proudly posted a message on Twitter last spring that featured the Razorbacks' new helmets - a futuristic design by Riddell called the SpeedFlex that is supposed to be the latest in head protection.

A vocal proponent of player safety, Bielema is happy to be a part of the cutting edge. But it's a bit of a leap of faith. He has no proof that the SpeedFlex - or any other helmet - can reduce the risk of a devastating head injury.

"It's just like everything else - everything advances and you get better at it," Bielema said at a recent Arkansas practice. "I think our kids really like the way (the helmets) feel. They feel snug. They feel fit. So I think that's a step in the right direction."

With lawsuits and concern regarding concussions hanging over every level of football, the race to develop safer helmets and other equipment has never been more intense. Even so, experts say it remains to be seen if new technology has made a dent in reducing concussions on the football field.

"It's very admirable that they're trying to get better," said Dr. Robert Cantu, a Boston-based neurosurgeon who specializes in sports concussions. "But with regards to concussions, it's a very complex issue ... There really isn't any helmet that has clearly been shown on the football field to be superior to other helmets."

The NCAA recently reached a proposed settlement of a class-action lawsuit by agreeing to toughen return-to-play rules for players who receive head blows and create a $70 million fund to pay for thousands of current and former athletes to undergo testing to determine whether they suffered brain trauma while playing football and other contact sports.

Concussions occur when the brain moves inside the skull from an impact or a whiplash effect, but it's still an injury that doctors are learning about. There's also debate about the best way to test for concussion factors or how to even identify when concussions occur.

The SpeedFlex's new design features a five-sided indentation on the crown of the helmet and a faceguard that both have some flexibility, which is supposed to allow some force to be absorbed and dispersed instead of going directly to the head.

There's also a revamped ratchet chinstrap system for faster adjustments and a quick release for the faceguard that could benefit medical staff seeking access to the face in the event of an emergency.

Thad Ide, Riddell's senior vice president for research and product development, said his company isn't claiming that the SpeedFlex can help reduce concussions. But like Bielema, he believes progress is being made in regards to lessening head impacts.

"We'll let the medical researchers weigh in on the medical data around concussions, because that's kind of a moving target right now because of all the things that are being learned," Ide said. "But what we can do is try to reduce the forces of impact to the player's head. I think reducing those forces is unequivocally a good thing."

Cantu said current football helmet certification tests by the National Operating Committee on Standards for Athletic Equipment (NOCSAE) measure only linear impacts, which are direct blows. But new standards proposed over the summer would also mandate tests for rotational forces - or non-direct blows that could better reflect what actually happens on a football field.

NOCSAE's new standards are expected to go into effect sometime next year.

Mike Oliver, the executive director of NOCSAE, said helmet technology is improving but there are no simple answers.

"I think the helmet manufactures are doing everything they can do to address these issues," Oliver said. "But they labor under the same restrictions that we do, which is until we understand more about the specifics of what causes a particular concussion, it's a little difficult."

Riddell spokeswoman Erin Griffin said more than half of NCAA Division I programs are using the SpeedFlex. She said some programs - like Arkansas - have taken an aggressive approach to using the helmets while others have more of a wait-and-see attitude.

Mississippi State equipment manager Phil Silva, who is in his 31st year at the school, said he had the opportunity to order the SpeedFlex but declined. He said the technology looked fine, but he wanted to make sure there was demand among players.

"Most of our players like to use the brand of helmet they used in high school," Silva said. "We want to make sure guys are going to use them before we order."

Dr. Stefan Duma, the department head of the Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, has been a pioneer in releasing independent ratings for the safety football helmets provide.

He says Riddell's newest modifications for the SpeedFlex are "promising," though he has not tested the helmet because it's not yet available to the public. His team tests helmets by purchasing three and then performing 40 tests on each helmet that measure front, top, side and back impacts.

They then aggregate the scores from all impacts and assign each helmet a 1-5 star rating, with a 5-star label being the highest.

"It's one of the first really new concepts in helmet technology - having the flexible outer shell," Duma said of the SpeedFlex.

Riddell provides helmets to every level of football - all the way from the pros to Pop Warner. Designing a helmet that successfully tests as a 'safer' model would be a boon for the manufacturer.

The company was previously the official helmet of the NFL, but that partnership ended after last season. A league spokesman said that in 2013, about 60 percent of the league's players used Riddell helmets.

For now, experts say the best way to make football safer is through rule changes. Dr. Julian Bailes, who has advised the NFLPA and NCAA about concussions and is the medical director for Pop Warner, says rules that outlaw targeting the head and limits on how often teams can have full-contact practices are vital advancements.

"Every level of play is addressing this issue," Bailes said. "Do you really need to be exposed to that many blows to the head?"